IBM 80 Customer Engineering Manual page 39

38
CARD SORTING MACHINE, TYPE 80
this relay is a high speed slate base relay. Its primary
function is to prevent starting of the machine by any
means other than the start key. This relay is picked
when the start key is depressed and remains energized as
long as the machine is running.
THE CCR-A
point,
in conjunction with card lever
contact 2, completes a hold circuit to the card control
relay and the motor relay. In its
NjO
condition, it pre-
vents the energization of either of the above relays ex-
cept by means of the start key in the event the machine
is stopped with cards in the feed.
THE CCR-B point prevents a back circuit which
would make the contact roll hot if the machine was
stopped with cards in the feed and the contact roll
cover was raised.
Brush Relay
This relay is a high speed slate base relay. Its pur-
pose is to provide a holding circuit for the sort magnet
from the time an impulse is sensed through a hole in
the card until the end of the card cycle when the cir-
cuit is broken by means of the commutator center ring
and brush.
Card Lever Contact 1
This contact closes as the leading edge of the card
enters the first feed rolls. Closing of this contact allows
sorting of the first card. Once closed, it remains closed
during the time that cards are feeding continuously
through the machine and, in conjunction with card
lever contact 2, furnishes circuits
to
the commutator
for sorting.
Card Lever Contact 2
This contact closes as the leading edge of the card
leaves the second feed roll. Once closed, it remains
closed during the time that cards are feeding con-
tinuously through the machine, and furnishes circuits
to the commutator for sorting and to the card control
relay and the motor relay for automatic operation.
This contact maintains the circuit to the commutator
and contact roll for sorting the last card.
Pocket Stop Contact
This contact is normally closed. Opening of this
contact, when one or more card pockets become full,
renders the runout circuit inoperative and causes im-
mediate dropout of the card control relay and the motor
relay. Dropout of these relays stOps the machine as
soon as its inertia is overcome by friction.
Contact Roll Cover Switches 1 and 2
These two switches are held in a closed position
when the contact roll cover is lowered. Raising of the
contact roll cover opens both switches, breaking all
machine circuits and remO\liing the potential from the
contact roll. These switches are installed as a safety
measure for operating personnel, and their operation
must not be crippled in any way.
5.0 Mfd Condenser
The action of the 5 mfd capacitor in series with the
sort magnet gives a large initial impulse
to
the sort
magnet when the card brush makes contact through
a hole in the card. This. causes fast attraction of the
armature, after which the current tapers off to hold
the sort magnet energized until the center brush on
the commutator breaks.